Diaphragm for phonograph sound-boxes.



P. WEBER.

DIAPHRAGM FOR PHONOGRAPH SOUND BOXES.

APPLICATION FILED MAY 24, 191s.

1,098,340. Patented May 26, 1914.

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BETER WEBER, OF OBAN GE, NEW JERSEY.

. AIDIAIEHRAGM FOR PHONOGRAPH SOUND-BOXES. i

Specification of Letters Patent.

Patented May 26, 1914.

Application led May 24, 1913. Serial No. 769,597. I

To all '107mm 'it may concern l Be it known that I, PETER WEBER, a citizen of the United States, residing in the city of Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Diaphragms for Ihonograph Sound-Boxes, of which the following 'is a full, clear, and exact description.

My invention relates to diaphragms and has for its object the provision of a central stift vibrating zone surrounded by an elastic, flexible, annular zone and it has for its 0bject the preservation of the clearness and distinctness of sound transmitted by the diaphragm as well as the obviation of the`de- Flection of sound waves and their consequent interference with one another.

It also has for a further object, the pro vision of `means whereby the diaphragm may be pro-perly centered within the sound box without Contact with the metallic portions thereof.

These and other objects will appear from the following detailed description taken in connection with the accompanying drawing, wherein-e Figure l illustrates a plan view of my improved diaphragm. Fig. 2 is a central or diametrical section of the diaphragm. Fig. 3 is a--vertical section through a sound box showing my improved diaphragmin position.

Similar reference numerals refer to like parts throughout the specification and drawg'Ihe diaphragm is composed of a thin sheet of metal or other suitable material of the` proper strength and elasticity. The central circular zone 1, is pressed into a shallow spherical shape, as clearly illustrated in Fig. 2. The surrounding annular zone 2, is slightly curved in cross sectionas shown, and unites with the margin of the central zone 1, in a cusp-like ridge or corrugation 3. The extreme margin of the diaphragm is reversely curved as at 4.

The sound box in which my improved diaphragm is mounted may be of any usual or preferred type; as for example that illustrated in the sound box is rovided with the hollow connecting thimb e 5, through which the sound waves, generated by the diaphragm are directed to the sound amplifier. -Withinthe sound box body, the annular gasket cross section in Fig. 3. In this case seat 6 is provided, said gasket seat being curved m., cross section to receive the ring gasket 7, which is circular in cross section. The curved margin 4 of the diaphragm rests upon and closely Iits the outer surface of the annular gasket 7, in such a manner that the extreme edge of the gasket does .not come 1n Contact with the metal portion of the sound box.

As will be readily seen the curved margin` 4, ts closely to the surface of the gasket ring 7, in such a manner as to properly center the diaphragm and when the outer gasket 8 and retaining ring 9 are in position, the diaphragm is held firmly in place without liability of contact between the edge of the diaphragm and the metal parts of the sound box.

I have not shown the usual stylus lever and stylus, and their connection with the dlaphragm, as they form no part of my present invention. rlhey may be of any usual or preferred type either for use in connection with what has come to be known as the disk phonograph or with the cylindrical .type of phonograph. v

It will be noted that the -cusp-like cor rugation or ridge 3 at the juncture of the central zone 1, and the annular zone 2, is wholly above a plane tangent to the-annular curved margin 4. I find that the location of the corrugation 3, above this plane gives better results'in the way of clearness and definition of tone'than when such ridge is located either coincident with or below thev plane tangent to the surface of the curved edge 4.

The making of the central zone 1, spherical or dished shaped, renders it substantially rigid and under the influence of the sound record with which the sound box is intended to be used, this central Zone vibrates as a whole so that the sound waves thus generated are transmitted in substantially direct lines. The annular '/.one 2 being highly elastic readily permits` this vibration of the central zone 1, sot-hat by the use of a diaphragm constructed in the manner described, the natural tone oi the sounds transmitted preserved with extreme clea-rness and dis- .'nctness and without sound-wave inter-fer ence.

From an inspection of Fig. 2 it will be noted that the disk from whicht-he diaphragm is formed is generally upwardly curved in cross-section and that the cusp-like corrugallO tion 3, is located substantially midway between the center and the circumference. of the disk. This general upward curve in cross-sectiono'f the disk is such that the apex of the corrugation 3 lies above the plane tangent to the reve'rsely curved margin t of the disk. i

I claim:

1. A diaphragm for sound boxes composed of a disk of resilient material formed into a central arc shaped zone, anda circular zone, said zones being united midway between the center and circumference of said` diaphragm in a cusp-like annular ridge,

1.5 Y said circular zone being curved in cross-sec ti'on and reversely curved atrits external cir# cumference. l

2. A diaphragm for sound boxes composed of a disk of strong elastic sheet metal ,2o/having its margin curved in cross section,

with an annular zone also curved in crossy section, and a central rigid zone, said zones being connected by a cusp-like annular ridge or corrugation. midway between .the centerv and circumference of said diaphragm.

3. A diaphragm for sound boxes composed of a disk of sheet metal having an annular cusp-like corrugation therein, midway between the center and the circumference of said disk, with the portions both within and without said corrugation upwardly curved in cross-section7 and the extreme margin ofthe disk reversely curved in cross-section.

4. A diaphragm for sound boxes, coinposed of a' thin disk of elastic sheet metal, having a central rigid zone surrounded by by an annular, flexible zone of equal radial width which is curved in cross-section and whose edge is reversely curved.

5. A diaphragm for sound boxes, com posed of a disk of resilient sheet metal, having a cusp-like annular corrugation therein midway betweenits center and circumference, with the portion wit-hin said corrugation upwardly arched or curved into a substantially spherical surface, and the portion without said corrugation upwardly curved and its edge reversel curved.

6. A diaphragm or sound boxes, comlposed of a disk of resilient sheet metal, up-

wardly curved in cross-section and having a single downwardly extending cusp-like annular corrugation midway between the ceuter and circumference of said disk, the apex ofsaid corrugation lying above a plane tangent to the surface of the edge of said disk.

In testimony whereof, I have hereunto set my-hand this 20th day of May, 1913.

v GEO. W. PERRY, L. M. SANDERS. 

